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Different methods have been used to predict soil properties and obtain continuous spatial distributions. However, studies that compare the accuracy of these methods are scarce. In addition, few studies considered human activity variables as well as landscape ecology variables to predict soil properties. The objective of this research was to determine the optimal method for predicting soil properties using human activity and landscape ecology variables in regions with complex topographies. The study results are as follows. (1) Introducing land-use type as human activity variable to the soillandscape model can improve the accuracy. (2) In the study region, the mean absolute error (MAE) and mean relative error (MRE) of the soil organic matter, pH, and soil particle size predicted by the soillandscape model were lower than those predicted by ordinary Kriging method. (3) Specifically, the regions in which the soil-landscape prediction model was more accurate were all concentrated in the central and west hilly regions in the study region, whereas the regions in which the geostatistical interpolation was more accurate were mainly in the east plain region. The differences in the results are based on the topography of the study area. [ABSTRACT FROM AUTHOR]

Background: We performed the present study to better elucidate the correlation of nitric oxide synthase 3 (NOS3) gene polymorphism with the risk of pulmonary arterial hypertension (PAH)., Material/methods: According to the designed search strategy, a systematic literature search was performed through the PubMed, Embase, Web of Science, Cochrane Library, CNKI, VIP and Wan Fang databases to collect published case-control studies on the correlation between NOS3 gene polymorphism and PAH. The search deadline was December 26, 2023. Two reviewers independently screened the literature, extracted data and evaluated the quality according to the inclusion and exclusion criteria. Meta-analysis was performed using RevMan 5.4 software. The odds ratio (OR) and 95 % confidence interval (CI) of the genotype distribution were used as the effect indicators., Results: A total of 11 eligible studies were included, involving three single nucleotide polymorphism (SNP) sites of the NOS3 gene: G894T (rs1799983), 4b/4a (rs61722009), and T-786C (rs2070744). The meta-analysis revealed that for PAH analysis, 4 genetic models of NOS3 G894T polymorphism increased the risk of PAH: the allele model (T vs G, OR = 1.9, 95%CI [1.16, 3.11],P = 0.01), the homozygote model (GG vs TT, OR = 1.91, 95%CI [1.04, 3.51], P = 0.04), the heterozygote model (GG vs GT, OR = 3.19, 95%CI [1.65, 6.19], P = 0.0006) and the dominant model (GT + TT vs GG, OR = 3.06, 95%CI [1.54, 6.09], P = 0.001). In the subgroups analysis, the NOS3 G894T polymorphism was found to be associated with the risk of PAH subgroups, including CHD combined with PAH and COPD combined with PAH, Particularly, there is a highly significant correlation with CHD combined with PAH. 2 genetic models of NOS3 4b/4a polymorphism increased the risk of PAH: the homozygote model (BB vs AA, OR = 2.1, 95%CI [1.02, 4.35], P = 0.04) and the recessive model (BB + BA vs AA, OR = 2.55, 95%CI [1.27, 5.11], P = 0.009). In the subgroups analysis, the NOS3 4b/4a polymorphism was found to be associated with the susceptibility of CHD combined with PAH. The results of the combined analysis of each gene model of NOS3 T-786C gene polymorphism sites were not statistically significant, and their P values were all>0.05. The NOS3 G894T and NOS3 4b/4a gene polymorphism had been found to be associated with the risk of PAH in different regional and racial subgroups. In contrast to the NOS3 G894T gene polymorphism, which increased the risk of PAH development in the yellow race subgroup, the NOS3 4b/4a gene polymorphism reduced the risk of PAH development in the white race subgroup and was a protective factor., Conclusions: The NOS3 G894T (rs1799983) and NOS3 4b/4a (rs61722009) gene polymorphism have a strong correlation with the risk of PAH, with this association varying among different regions and ethnicities. However, it is still necessary to expand the sample size and conduct further studies to confirm whether the NOS3 T-786C (rs2070744) polymorphism tends to increase the incidence of PAH., Competing Interests: Conflict of interest The authors declared that there have no conflicts of interest to this work., (Copyright © 2024 Elsevier Inc. All rights reserved.)

In this paper, four novel hydrazine fluorescent probes X 1 -X 4 with bis-chalcone structure were designed and synthesized. Through the measurement of its optical properties, it is found that it can quickly identify hydrazine, high sensitivity, low detection limit, and good anti-interference ability. The recognition of hydrazine by probes X 1 -X 4 is not affected in the pH range of 4-10, X 2 has the highest sensitivity, and the detection limit is as low as 0.336 × 10 -7 M. Through Gaussian quantization calculation of probe molecules and their reaction products with hydrazine, it is speculated that the recognition mechanism is the closure of intramolecular charge transfer effect. In addition, the cytotoxicity and imaging of HeLa cells were tested, which showed that probes X 1 -X 4 could be used to detect hydrazine in cells., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Rodents have been confirmed as hosts of various vector-borne zoonotic pathogens and are important for the maintenance of these microbes in nature. However, surveillance for zoonotic pathogens is limited for many wild rodent species in China, so our knowledge of pathogen ecology, genetic diversity, and the risk of cross-species transmission to humans is limited. In this study, 165 spleen samples of Daurian ground squirrels ( Spermophilus dauricus ) were collected from Weichang Manchu and the Mongolian Autonomous County of Hebei Province, China, and Rickettsia , Bartonella , and Anaplasma were identified by DNA detection using polymerase chain reaction (PCR). Sequence analysis identified eight bacterial pathogens: R. raoultii , R. sibirica , Candidatus R. longicornii, B. washoensis , B. grahamii , B. jaculi , A. capra , and Candidatus Anaplasma cinensis. Co-infection of B. grahamii and R. raoultii in one sample was observed. Our results demonstrated the genetic diversity of bacteria in Daurian ground squirrels and contributed to the distribution of these pathogens. Six species, A. capra , R. raoultii , R. sibirica , Candidatus R. longicornii, B. washoensis , and B. grahamii , are known to be pathogenic to humans, indicating a potential public health risk to the local human population, especially to herders who frequently have close contact with Daurian ground squirrels and are thus exposed to their ectoparasites., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Xue, Chen, Xu, Wang, Wang, Diao, Du, Xie and Guo.)

Background: Dogs and cats are the hosts of many vector-borne human pathogens that can be transmitted to humans. Given their direct and intimate contact with humans, companion dogs and cats are considered direct sentinels of vector-borne human pathogens. However, limited information is currently available regarding canine and feline zoonotic pathogens in China. This study detected canine and feline vector-borne human pathogens to better understand the potential risk to humans., Methods: Blood samples were collected from 275 domestic companion animals (117 dogs and 158 cats) living in Tianjin city, China, and the presence of DNA from Anaplasma , Babesia , Bartonella , and Rickettsia was detected by semi-nested polymerase chain reaction (PCR). The PCR products of the expected size were sequenced, and these newly generated sequences were subjected to BLASTN, nucleotide identity, and phylogenetic analyses., Results: A total of 24 blood samples tested positive for vector-borne pathogens in companion dogs and cats in Tianjin city, China, with a relatively low positive rate of 8.7%. Specifically, seven human pathogens, including Rickettsia raoultii , Candidatus Rickettsia jingxinensis , Rickettsia sibirica , Rickettsia felis , Babesia venatorum , Bartonella tribocorum , and Bartonella Henselae , were identified. In addition, Anaplasma ovis with zoonotic potential and Candidatus A. cinensis were detected., Conclusion: Our results indicate substantial genetic diversity in the vector-borne human pathogens circulating in companion dogs and cats. Interventions based on "One Health" should be taken to reduce the potential risks of contracting infection from companion dogs and cats in Tianjin, China., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Jian, Xue, Xu, Chen, Wang, Du, Xie and Guo.)

Aim: This paper aimed to explore the application of three-dimensional (3D) printing in cardiovascular diseases, to reach an insight in this field and prospect the future trend., Methods: The articles were selected from the Web of Science Core Collection database. Excel 2019, VOSviewer 1.6.16, and CiteSpace 6.1.R6 were used to analyze the information., Results: A total of 467 papers of 3D printing in cardiovascular diseases were identified, and the first included literature appeared in 2000. A total of 692 institutions from 52 countries participated in the relevant research, while the United States of America contributed to 160 articles and were in a leading position. The most productive institution was Curtin University , and Zhonghua Sun who has posted the most articles ( n =8) was also from there. The Frontiers in Cardiovascular Medicine published most papers ( n =25). The Journal of Thoracic and Cardiovascular Surgery coveted the most citations ( n =520). Related topics of frontiers will still focus on congenital heart disease, valvular heart disease, and left atrial appendage closure., Conclusions: The authors summarized the publication information of the application of 3D printing in cardiovascular diseases related literature from 2000 to 2023, including country and institution of origin, authors, and publication journal. This study can reflect the current hotspots and novel directions for the application of 3D printing in cardiovascular diseases., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.)

A fluorescent probe Y((1,1'-([1,1'-biphenyl]-4,4'-diylbis(3-(2-hydroxyphenyl)-4,5-dihydro-1H-pyrazole-5,1-diyl)) bis(ethan-1-one))) was designed and synthesized, which could be used to Cu 2+ and Fe 3+ sensors. Through the study of optical properties, the probe Y shows good selectivity and sensitivity to Cu 2+ and Fe 3+ in aqueous tetrahydrofuran solution [10.0 mM HEPES, pH 7.4, THF-H 2 O = 9:1(v/v)] with has excellent anti-interference performance, and its detection limits were 0.931 uΜ for Cu 2+ and 0.401uΜ for Fe 3+ . The coordination mechanism of probe Y with Cu 2+ and Fe 3+ was speculated and verified at DFT level and HRNM. By Hela cytotoxicity and imaging tests, probe Y not only has good biocompatibility, but also can be used for sensing Cu 2+ in cells., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: The distinction between solitary inflammatory lesion and solitary lung cancer remains a challenge because of their considerable overlapping computed tomography (CT) imaging features., Purpose: This study aimed to verify whether spectral CT parameters can differentiate solitary lung cancer from solitary inflammatory lesions and to find their correlations with lesion size., Methods: A total of 78 patients with solitary lung lesions were included in our study. All of them underwent enhanced CT scans with Gemstone Spectral Imaging (GSI) mode, which was one of the dual-energy imaging technologies. According to maximum diameter (Dmax) of the lesion, regions of interest were collected and divided into inflammatory (group I: <3 cm [IA], n = 17; ≥3 cm [IB], n = 14) and cancer groups (group II: <3 cm [IIA], n = 20; ≥3 cm [IIB], n = 27). Computed tomography values (HU40keV, HU70keV), effective atomic number (Zeff), iodine concentration (IC), normalized IC (NIC), and spectral curve slopes (λ30, λ40) of each region of interest were calculated. The NIC was defined as the IC ratio of the lesion to the descending aorta. Mann-Whitney U test was used for intergroup (I vs II, IA vs IIA, IB vs IIB) and intragroup (IA vs IB, IIA vs IIB) comparisons, and receiver operating characteristic curve analysis was performed. Correlation analysis was applied to find the relationship between Dmax and GSI parameters., Results: No significant correlation was found between GSI parameters and Dmax in the inflammatory group, whereas inverse correlations were found in the cancer group. Gemstone spectral imaging parameters (except HU70keV) of group IIA were significantly higher than those of group IIB. There were significant differences in HU40keV, IC, NIC, λ30, and λ40 between groups IB and IIB under both arterial and venous phase (P values < 0.05), whereas the area under the curve for λ30 under venous phase was largest, and sensitivity and specificity were 96.32% and 85.71%, respectively. However, only HU40keV and HU70keV values under the arterial phase of IIA were significantly higher than those of IA., Conclusions: Quantitative parameters of GSI demonstrated an inverse correlation with the lesion size of solitary lung cancer, and GSI parameters can be new ways to differentiate solitary lung cancer from solitary inflammatory lesions., Competing Interests: The authors declare no conflict of interest. The research is partially supported by Planning Project Grand (3502Z20174012) and Guiding Project Grand (3502Z20199040) from the Xiamen Municipal Bureau of Science and Technology (CN)., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

The accuracy in diagnosing prostate cancer (PCa) has increased with the development of multiparametric magnetic resonance imaging (mpMRI). Biparametric magnetic resonance imaging (bpMRI) was found to have a diagnostic accuracy comparable to mpMRI in detecting PCa. However, prostate MRI assessment relies on human experts and specialized training with considerable inter-reader variability. Deep learning may be a more robust approach for prostate MRI assessment. Here we present a method for autosegmenting the prostate zone and cancer region by using SegNet, a deep convolution neural network (DCNN) model. We used PROSTATEx dataset to train the model and combined different sequences into three channels of a single image. For each subject, all slices that contained the transition zone (TZ), peripheral zone (PZ), and PCa region were selected. The datasets were produced using different combinations of images, including T2-weighted (T2W) images, diffusion-weighted images (DWI) and apparent diffusion coefficient (ADC) images. Among these groups, the T2W + DWI + ADC images exhibited the best performance with a dice similarity coefficient of 90.45% for the TZ, 70.04% for the PZ, and 52.73% for the PCa region. Image sequence analysis with a DCNN model has the potential to assist PCa diagnosis.

Classifying mental disorder is a big issue in psychology in recent years. This article focuses on offering a relation between decision tree and encoding of fMRI that can simplify the analysis of different mental disorders and has a high ROC over 0.9. Here we encode fMRI information to the power-law distribution with integer elements by the graph theory in which the network is characterized by degrees that measure the number of effective links exceeding the threshold of Pearson correlation among voxels. When the degrees are ranked from low to high, the network equation can be fit by the power-law distribution. Here we use the mentally disordered SHR and WKY rats as samples and employ decision tree from chi2 algorithm to classify different states of mental disorder. This method not only provides the decision tree and encoding, but also enables the construction of a transformation matrix that is capable of connecting different metal disorders. Although the latter attempt is still in its fancy, it may have a contribution to unraveling the mystery of psychological processes.

Antiangiogenic therapy is widely administered in many cancers, and the antiangiogenic drug sorafenib offers moderate benefits in advanced hepatocellular carcinoma (HCC). However, antiangiogenic therapy can also lead to hypoxia-driven angiogenesis and immunosuppression in the tumor microenvironment (TME) and metastasis. Here, we report the synthesis and evaluation of NanoMnSor, a tumor-targeted, nanoparticle drug carrier that efficiently codelivers oxygen-generating MnO 2 and sorafenib into HCC. We found that MnO 2 not only alleviates hypoxia by catalyzing the decomposition of H 2 O 2 to oxygen but also enhances pH/redox-responsive T1-weighted magnetic resonance imaging and drug-release properties upon decomposition into Mn 2+ ions in the TME. Moreover, macrophages exposed to MnO 2 displayed increased mRNA associated with the immunostimulatory M1 phenotype. We further show that NanoMnSor treatment leads to sorafenib-induced decrease in tumor vascularization and significantly suppresses primary tumor growth and distal metastasis, resulting in improved overall survival in a mouse orthotopic HCC model. Furthermore, NanoMnSor reprograms the immunosuppressive TME by reducing the hypoxia-induced tumor infiltration of tumor-associated macrophages, promoting macrophage polarization toward the immunostimulatory M1 phenotype, and increasing the number of CD8 + cytotoxic T cells in tumors, thereby augmenting the efficacy of anti-PD-1 antibody and whole-cell cancer vaccine immunotherapies. Our study demonstrates the potential of oxygen-generating nanoparticles to deliver antiangiogenic agents, efficiently modulate the hypoxic TME, and overcome hypoxia-driven drug resistance, thereby providing therapeutic benefit in cancer.

Background: Gadolinium-based contrast agents can be used to identify the blood-brain barrier (BBB) opening after inducing a focused ultrasound (FUS) cavitation effect in the presence of microbubbles. However, the use of gadolinium may be limited for frequent routine monitoring of the BBB opening in clinical applications., Purpose: To use a gradient-echo sequence without contrast agent administration for monitoring of acoustic cavitation., Study Type: Animal and phantom prospective., Phantom/animal Model: Static and flowing gel phantoms; six normal adult male Sprague-Dawley rats., Field Strength/sequence: 3T, 7T; fast low-angle shot sequence., Assessment: Burst FUS with acoustic pressures = 1.5, 2.2, 2.8 MPa; pulse repetition frequencies = 1, 10,100 Hz; and duty cycles = 2%, 5%, 10% were transmitted to the chamber of a static phantom with microbubble concentrations = 10%, 1%, 0.1%. MR slice thicknesses = 3, 6, 8 mm were acquired. In flowing phantom experiments, 0.1%, 0.25%, 0.5%, 0.75%, and 1% microbubbles were infused and transmitted by burst FUS with an acoustic pressure = 0.4 and 1 MPa. In in vivo experiments, 0.25% microbubbles was infused and 0.8 MPa burst FUS was transmitted to targeted brain tissue beneath the superior sagittal sinus. The mean signal intensity (SI) was normalized using the mean SI from pre-FUS., Statistical Tests: Two-tailed Student's t-test. P < 0.05 was considered statistically significant., Results: In the static phantom, the time courses of normalized SI decreases to minimum SI levels of 70-80%. In the flowing phantom, substantial normalized SI of 160-230% was present with variant acoustic pressures and microbubble concentrations. Compared with in vivo control rats, the brain tissue of experimental rats with transmission of FUS pulses exhibited considerable decreases of normalized SI (P < 0.001) because of the cavitation-induced perturbation of flow., Data Conclusion: Observing gradient-echo SI changes can help monitor the targeted location of microbubble-enhanced FUS, which in turn assists the monitoring of the BBB opening., Level of Evidence: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2020;51:311-318., (© 2019 International Society for Magnetic Resonance in Medicine.)

Abnormal tumour vasculature has a significant impact on tumour progression and response to therapy. Nitric oxide (NO) regulates angiogenesis and maintains vascular homeostasis and, thus, can be delivered to normalize tumour vasculature. However, a NO-delivery system with a prolonged half-life and a sustained release mechanism is currently lacking. Here we report the development of NanoNO, a nanoscale carrier that enables sustained NO release to efficiently deliver NO into hepatocellular carcinoma. Low-dose NanoNO normalizes tumour vessels and improves the delivery and effectiveness of chemotherapeutics and tumour necrosis factor-related, apoptosis-inducing, ligand-based therapy in both primary tumours and metastases. Furthermore, low-dose NanoNO reprogrammes the immunosuppressive tumour microenvironment toward an immunostimulatory phenotype, thereby improving the efficacy of cancer vaccine immunotherapy. Our findings demonstrate the ability of nanoscale NO delivery to efficiently reprogramme tumour vasculature and immune microenvironments to overcome resistance to cancer therapy, resulting in a therapeutic benefit.

Background: Proximal symphalangism is a rare disease with multiple phenotypes including reduced proximal interphalangeal joint space, symphalangism of the 4th and/or 5th finger, as well as hearing loss. At present, at least two types of proximal symphalangism have been identified in the clinic. One is proximal symphalangism-1A (SYM1A), which is caused by genetic variants in Noggin (NOG), another is proximal symphalangism-1B (SYM1B), which is resulted from Growth Differentiation Factor 5 (GDF5) mutations., Case Presentation: Here, we reported a Chinese family with symphalangism of the 4th and/or 5th finger and moderate deafness. The proband was a 13-year-old girl with normal intelligence but symphalangism of the 4th finger in the left hand and moderate deafness. Hearing testing and inner ear CT scan suggested that the proband suffered from structural deafness. Family history investigation found that her father (II-3) and grandmother (I-2) also suffered from hearing loss and symphalangism. Target sequencing identified a novel heterozygous NOG mutation, c.690C > G/p.C230W, which was the genetic lesion of the affected family. Bioinformatics analysis and public databases filtering further confirmed the pathogenicity of the novel mutation. Furthermore, we assisted the family to deliver a baby girl who did not carry the mutation by genetic counseling and prenatal diagnosis using amniotic fluid DNA sequencing., Conclusion: In this study, we identified a novel NOG mutation (c.690C > G/p.C230W) by target sequencing and helped the family to deliver a baby who did not carry the mutation. Our study expanded the spectrum of NOG mutations and contributed to genetic diagnosis and counseling of families with SYM1A.

Background: This study evaluated the performance of histogram analysis in the time course of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for differentiating cancerous tissues from benign tissues in the prostate., Methods: We retrospectively analyzed the histograms of DCE-MRI of 30 patients. Histograms within regions of interest(ROI) in the peripheral zone (PZ) and transitional zone (TZ) were separately analyzed. The maximum difference wash-in slope (MWS) and delay phase slope (DPS) were defined for each voxel. Differences in histogram parameters, namely the mean, standard deviation (SD), the coefficient of variation (CV), kurtosis, skewness, interquartile range (IQR), percentile (P10, P25, P75, P90, and P90P10), Range, and modified full width at half-maximum (mFWHM) between cancerous and benign tissues were assessed., Results: In the TZ, CV for ROIs of 7.5 and 10mm was the only significantly different parameter of the MWS (P = 0.034 and P = 0.004, respectively), whereas many parameters of the DPS (mean, skewness, P10, P25, P50, P75 and P90) differed significantly (P = <0.001-0.016 and area under the curve [AUC] = 0.73-0.822). In the PZ, all parameters of the MWS exhibited significant differences, except kurtosis and skewness in the ROI of 7.5mm(P = <0.001-0.017 and AUC = 0.865-0.898). SD, IQR, mFWHM, P90P10 and Range were also significant differences in the DPS (P = 0.001-0.035)., Conclusion: The histogram analysis of DCE-MRI is a potentially useful approach for differentiating prostate cancer from normal tissues. Different histogram parameters of the MWS and DPS should be applied in the TZ and PZ., Competing Interests: The authors have declared that no competing interests exist.

The location of an acute ischemic stroke is associated with its prognosis. The widely used Gaussian model-based parameter, apparent diffusion coefficient (ADC), cannot reveal microstructural changes in different locations or the degree of infarction. This prospective observational study was reviewed and approved by the Institutional Review Board of Xiamen Second Hospital, China (approval No. 2014002).Diffusion kurtosis imaging (DKI) was used to detect 199 lesions in 156 patients with acute ischemic stroke (61 males and 95 females), mean age 63.15 ± 12.34 years. A total of 199 lesions were located in the periventricular white matter (n = 52), corpus callosum (n = 14), cerebellum (n = 29), basal ganglia and thalamus (n = 21), brainstem (n = 21) and gray-white matter junctions (n = 62). Percentage changes of apparent diffusion coefficient (ΔADC) and DKI-derived indices (fractional anisotropy [ΔFA], mean diffusivity [ΔMD], axial diffusivity [ΔD a ], radial diffusivity ΔD r , mean kurtosis [ΔMK], axial kurtosis [ΔK a ], and radial kurtosis [ΔK r ]) of each lesion were computed relative to the normal contralateral region. The results showed that (1) there was no significant difference in ΔADC, ΔMD, ΔD a or ΔD r among almost all locations. (2) There was significant difference in ΔMK among almost all locations (except basal ganglia and thalamus vs. brain stem; basal ganglia and thalamus vs. gray-white matter junctions; and brainstem vs. gray-white matter junctions. (3) The degree of change in diffusional kurtosis in descending order was as follows: corpus callosum > periventricular white matter > brainstem > gray-white matter junctions > basal ganglia and thalamus > cerebellum. In conclusion, DKI could reveal the differences in microstructure changes among various locations affected by acute ischemic stroke, and performed better than diffusivity among all groups., Competing Interests: None

The electron localization in Nb-doped CaMnO3 is analyzed in terms of the space and energy distribution of electronic states employing first-principles calculations. The energy difference of Mn 3d states and Nb 4d states makes NbO6 octahedra impede electrical conduction, so the random distribution of Nb in lattices leads to the localization of electrons near the bottom of the conduction bands. Therefore, although more carriers are introduced when Nb-doping content increases, both the electrical conductivity and absolute thermopower decrease in Nb heavy doped CaMnO3. The calculated transport properties agree well with the experimental data, supporting the analysis of localization.

Interplay of hormones with reactive oxygen species (ROS) fine-tunes the response of plants to stress; however, the crosstalk between brassinosteroids (BRs) and ROS in nematode resistance is unclear. In this study, we found that low BR biosynthesis or lack of BR receptor increased, whilst exogenous BR decreased the susceptibility of tomato plants to Meloidogyne incognita. Hormone quantification coupled with hormone mutant complementation experiments revealed that BR did not induce the defence response by triggering salicylic acid (SA), jasmonic acid/ethylene (JA/ET) or abscisic acid (ABA) signalling pathway. Notably, roots of BR-deficient plants had decreased apoplastic ROS accumulation, transcript of RESPIRATORY BURST OXIDASE HOMOLOG1 (RBOH1) and WHITEFLY INDUCED1 (WFI1), and reduced activation of mitogen-activated protein kinase 1/2 (MPK1/2) and MPK3. Silencing of RBOH1, WFI1, MPK1, MPK2 and MPK3 all increased the root susceptibility to nematode and attenuated BR-induced resistance against the nematode. Significantly, suppressed transcript of RBOH1 compromised BR-induced activation of MPK1/2 and MPK3. These results strongly suggest that RBOH-dependent MPK activation is involved in the BR-induced systemic resistance against the nematode., (© 2017 John Wiley & Sons Ltd.)

The gadolinium-doped iron oxide nanoparticles (GdIONP) with greater specific power adsorption rate (SAR) than Fe 3 O 4 was developed and its potential application in tumour therapy and particle tracking were demonstrated in transgenic adenocarcinoma of the mouse prostate C1 (TRAMP-C1) tumours. The GdIONPs accumulated in tumour region during the treatment could be clearly tracked and quantified by T2-weighted MR imaging. The therapeutic effects of GdIONP-mediated hyperthermia alone or in combination with radiotherapy (RT) were also evaluated. A significant increase in the tumour growth time was observed following the treatment of thermotherapy (TT) only group (2.5 days), radiation therapy only group (4.5 days), and the combined radio-thermotherapy group (10 days). Immunohistochemical staining revealed a reduced hypoxia region with vascular disruption and extensive tumour necrosis following the combined radio-thermotherapy. These results indicate that GdIONP-mediated hyperthermia can improve the efficacy of RT by its dual functions in high temperature (temperature greater than 45 °C)-mediated thermal ablation and mild-temperature hyperthermia (MTH) (temperature between 39 and 42 °C)-mediated reoxygenation.

Purpose: To measure wall shear stress (WSS) in the common carotid arteries (CCA) of a spontaneously hypertensive rat (SHR) model and a normotensive Wistar Kyoto rat (WKY) model by 2D phase-contrast magnetic resonance imaging (PC-MRI)., Materials and Methods: PC-MRI was performed on 7 SHR and 7 WKY at ages of 4 and 7months at a 7T scanner. Images in the middle CCA (CCAmid) and in the bifurcation of CCA (CCAbifur) were acquired. The WSS values for differentiating characteristics between two models were calculated. Further, its location-specific change, regional distribution along the CCA circumference, and the reproducibility were evaluated., Results: In the 4-month-old rats, SHR showed lower temporal averaged WSS (WSSavg) and peak systolic WSS (WSSs) in the CCAbifur in comparison with WKY (WSSavg: 0.95±0.18 vs. 1.30±0.36N/m(2) (P<0.01); WSSs: 1.68±0.70 vs. 3.22±2.49N/m(2) (P<0.05)). We observed the same trends in the 7-month-old rats. In the SHR model, the WSSavg was lower in the CCAbifur than in the CCAmid. The regional distribution of WSSavg along the circumference of CCA showed lower values in WKY, particularly in posterior segments of CCAbifur. The intra-observer, intra-scan and inter-scan reproducibility was acceptable and the disagreements were ranged from -0.05 to 0.06N/m(2)., Conclusion: This study evaluated WSS in SHR and WKY models by 2D PC-MRI. High reproducibility analyses further indicated the reliability of measurements of WSS in the CCA of SHR and WKY models using PC-MRI at 7T., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Plant vacuoles serve as the primary intracellular compartments for inorganic phosphate (Pi) storage. Passage of Pi across vacuolar membranes plays a critical role in buffering the cytoplasmic Pi level against fluctuations of external Pi and metabolic activities. Here we demonstrate that the SPX-MFS proteins, designated as PHOSPHATE TRANSPORTER 5 family (PHT5), also named Vacuolar Phosphate Transporter (VPT), function as vacuolar Pi transporters. Based on (31)P-magnetic resonance spectroscopy analysis, Arabidopsis pht5;1 loss-of-function mutants accumulate less Pi and exhibit a lower vacuolar-to-cytoplasmic Pi ratio than controls. Conversely, overexpression of PHT5 leads to massive Pi sequestration into vacuoles and altered regulation of Pi starvation-responsive genes. Furthermore, we show that heterologous expression of the rice homologue OsSPX-MFS1 mediates Pi influx to yeast vacuoles. Our findings show that a group of Pi transporters in vacuolar membranes regulate cytoplasmic Pi homeostasis and are required for fitness and plant growth.

Genetic divergences among mammalian strains are presented phenotypically in various aspects of physical appearance such as body shape and facial features. Yet how genetic diversity is expressed in brain function still remains unclear. Functional connectivity has been shown to be a valuable approach in characterizing the relationship between brain functions and behaviors. Alterations in the brain default mode network (DMN) have been found in human neuropsychological disorders. In this study we selected the spontaneously hypertensive rat (SHR) and the Wistar Kyoto rat (WKY), two inbred rat strains with close genetic origins, to investigate variations in the DMN. Our results showed that the major DMN differences are the activities in hippocampal area and caudate putamen region. This may be correlated to the hyperactive behavior of the SHR strain. Advanced animal model studies on variations in the DMN may have potential to shed new light on translational medicine, especially with regard to neuropsychological disorders.

Chemical exchange saturation transfer magnetic resonance imaging (CEST-MRI) is capable of both microenvironment and molecular imaging. The optimization of scanning parameters is important since the CEST effect is sensitive to factors such as saturation power and field homogeneity. The aim of this study was to determine if the CEST effect would be altered by changing the length of readout RF pulses. Both theoretical computer simulation and phantom experiments were performed to examine the influence of readout RF pulses. Our results showed that the length of readout RF pulses has unremarkable impact on the Z-spectrum and CEST effect in both computer simulation and phantom experiment. Moreover, we demonstrated that multiple refocusing RF pulses used in rapid acquisition with relaxation enhancement (RARE) sequence induced no obvious saturation transfer contrast. Therefore, readout RF pulse has negligible effect on CEST Z-spectrum and the optimization of readout RF pulse length can be disregarded in CEST imaging protocol.

Background: Whole-brain cerebral blood flow (CBF) measured by phase-contrast MRI (PC-MRI) provides an important index for brain function. This work aimed to optimize the PC-MRI imaging protocol for accurate CBF measurements., Methods: Two studies were performed on a 3 Tesla system. In Study 1 (N = 12), we optimized in-plane resolution of PC-MRI acquisition for CBF quantification by considering accuracy, precision, and scan duration. In Study 2 (N = 7), we assessed the detrimental effect of nonperpendicular imaging slice orientation on CBF quantification. Both One-way analysis of variance with repeated measurement and Friedman test were used to examine the effects of resolution and angulation on CBF quantification. Additionally, we evaluated the inter-rater reliability in PC-MRI data processing., Results: Our results showed that CBF measurement with 0.7 mm resolution could be overestimated by up to 13.3% when compared with 0.4 mm resolution. Moreover, CBF could also be overestimated by up to 18.8% when the slice orientation is deviated by 30° from the ideal angulation. However, within 10° of the ideal slice orientation, estimated CBF was not significantly different from each other (P = 0.23 and 0.45 for internal carotid artery and vertebral artery, respectively). Inter-rater difference was <3%., Conclusion: For fast and accurate quantification of whole-brain CBF with PC-MRI, we recommend the use of an imaging resolution of 0.5 mm and a slice orientation that is less than 10° from vessel's axial plane., (© 2015 Wiley Periodicals, Inc.)

The susceptibility differences at the gas-liquid interface of microbubbles (MBs) allow their use as an intravascular susceptibility contrast agent for in vivo MRI. However, the characteristics of MBs are very different from those of the standard gadolinium-diethylenetriaminepentaacetic acid (Gd-DPTA) contrast agent, including the size distribution and hemodynamic properties, which could influence MRI outcomes. Here, we investigate quantitatively the correlation between the relative cerebral blood volume (rCBV) derived from Gd-DTPA (rCBV(Gd)) and the MB-induced susceptibility effect (ΔR(2*MB)) by conventional dynamic susceptibility contrast MRI (DSC-MRI). Custom-made MBs had a mean diameter of 0.92 µm and were capable of inducing 4.68 ± 3.02% of the maximum signal change (MSC). The MB-associated ΔR(2*MB) was compared with rCBV(Gd) in 16 rats on 4.7-T MRI. We observed a significant effect of the time to peak (TTP) on the correlation between ΔR(2*MB) and rCBV(Gd), and also found a noticeable dependence between TTP and MSC. Our findings suggest that MBs with longer TTPs can be used for the estimation of rCBV by DSC-MRI, and emphasize the critical effect of TTP on MB-based contrast MRI., (Copyright © 2013 John Wiley & Sons, Ltd.)

Deuterium oxide (D2 O), which is commercially available and nonradioactive, was proposed as a perfusion tracer before the clinical usage of conventional gadolinium-based MRI contrast agents. However, the sensitivity of direct deuterium detection is the major challenge for its application. In this study, we propose a contrast-enhanced strategy to indirectly trace administered D2 O by monitoring the signal attenuation of (1) H MRI. Experiments on D2 O concentration phantoms and in vivo rat brains were conducted to prove the concept of the proposed contrast mechanism. An average maximum signal drop ratio of 5.25 ± 0.91% was detected on (1) H MR images of rat brains with 2 mL of D2 O administered per 100 g of body weight. As a diffusible tracer for perfusion, D2 O infusion is a practicable method for the assessment of tissue perfusion and has the potential to provide different information from gadolinium-based contrast agents, which have limited permeability for blood vessels. Furthermore, the observed negative relaxivities of D2 O reveal the (1) H-D exchange effect. Therefore, applications of perfusion MRI with D2 O as a contrast agent are worthy of further investigation., (Copyright © 2013 John Wiley & Sons, Ltd.)

In this study, the laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was adopted to determine the distribution of inorganic elements, including Ca, Cu, Fe, Mg, Mn, S, P, Pb, and Zn, in honeybees (Apis melifera L.). Two features are particularly noteworthy. First, it was found there is a significant amount of Fe located at the fringe of the abdomen in worker bees; ultrasonic imaging, scanning electron microscopy, and magnetic resonance imaging revealed that it arose from magnetic Fe-bearing nanoparticles (NPs) having an average diameter of approximately 40 nm. Interestingly, only worker bees contained these magnetic Fe-bearing NPs; no similar features appeared in larvae, pupae, wasps, or drones. Second, a detectable amount of Pb accumulated particularly in the alimentary canals of worker bees. Again, no detectable amounts of Pb in larvae, pupae, drones, or wasps, yet a level of 0.24 ± 0.05 mg/kg of Pb in pollen; therefore, the diet appears to be the primary pathway for environmental pollutants entering the honeybees' food chain.

Background and Purpose: The combination of phase demodulation and field mapping is a practical method to correct echo planar imaging (EPI) geometric distortion. However, since phase dispersion accumulates in each phase-encoding step, the calculation complexity of phase modulation is Ny-fold higher than conventional image reconstructions. Thus, correcting EPI images via phase demodulation is generally a time-consuming task., Methods: Parallel computing by employing general-purpose calculations on graphics processing units (GPU) can accelerate scientific computing if the algorithm is parallelized. This study proposes a method that incorporates the GPU-based technique into phase demodulation calculations to reduce computation time. The proposed parallel algorithm was applied to a PROPELLER-EPI diffusion tensor data set., Results: The GPU-based phase demodulation method reduced the EPI distortion correctly, and accelerated the computation. The total reconstruction time of the 16-slice PROPELLER-EPI diffusion tensor images with matrix size of 128 × 128 was reduced from 1,754 seconds to 101 seconds by utilizing the parallelized 4-GPU program., Conclusions: GPU computing is a promising method to accelerate EPI geometric correction. The resulting reduction in computation time of phase demodulation should accelerate postprocessing for studies performed with EPI, and should effectuate the PROPELLER-EPI technique for clinical practice., (Copyright © 2011 by the American Society of Neuroimaging.)

Dynamic contrast-enhanced MRI (DCE MRI) has been used to study tumor response to treatment for many years. In this study, the modified full width at half-maximum (mFWHM), calculated from the wash-in slope histogram, is proposed as a parameter for the evaluation of changes in tumor heterogeneity which respond to radiotherapy. Twenty-five patients with brain tumors were evaluated and divided into the nonresponder group (n = 11) and the responder group (n = 14) according to the Response Evaluation Criteria in Solid Tumors (RECIST). All selected tumors were evaluated by mFWHM ratios of post- to pre-therapy (the ratio was defined as the therapeutic mFWHM ratio, TMR). The changes in kurtosis of the histograms and the averaged K(trans) within a tumor were also calculated for comparison. The receiver operating characteristic analysis and Kaplan-Meier curves were used to examine the diagnosis ability. The TMR values were significantly higher in nonresponders than in responders (p < 0.001). When compared with the other two parameters, the proposed method also demonstrated better sensitivity and specificity. When adopting the TMR for the estimation of prognosis after therapy, there was a significant difference between the population survival curves. In conclusion, the derived mFWHM reflects tumor heterogeneity, and the ability to depict patient survival probability from TMR corresponds well with that from RECIST. The results reveal that, in brain tumors, progression may be exhibited not only by tumor size, but also by tumor heterogeneity., (Copyright © 2012 John Wiley & Sons, Ltd.)

Objective: This study investigates the application of a modified reversed gradient algorithm to the Propeller-EPI imaging method (periodically rotated overlapping parallel lines with enhanced reconstruction based on echo-planar imaging readout) for corrections of geometric distortions due to the EPI readout., Materials and Methods: Propeller-EPI acquisition was executed with 360-degree rotational coverage of the k-space, from which the image pairs with opposite phase-encoding gradient polarities were extracted for reversed gradient geometric and intensity corrections. The spatial displacements obtained on a pixel-by-pixel basis were fitted using a two-dimensional polynomial followed by low-pass filtering to assure correction reliability in low-signal regions. Single-shot EPI images were obtained on a phantom, whereas high spatial resolution T2-weighted and diffusion tensor Propeller-EPI data were acquired in vivo from healthy subjects at 3.0 Tesla, to demonstrate the effectiveness of the proposed algorithm., Results: Phantom images show success of the smoothed displacement map concept in providing improvements of the geometric corrections at low-signal regions. Human brain images demonstrate prominently superior reconstruction quality of Propeller-EPI images with modified reversed gradient corrections as compared with those obtained without corrections, as evidenced from verification against the distortion-free fast spin-echo images at the same level., Conclusions: The modified reversed gradient method is an effective approach to obtain high-resolution Propeller-EPI images with substantially reduced artifacts.

To implement a flow-gating method to acquire phase-contrast (PC) images of carotid arteries without use of an electrocardiography (ECG) signal to synchronize the acquisition of imaging data with pulsatile arterial flow. The flow-gating method was realized through radial scanning and sophisticated post-processing methods including downsampling, complex difference, and correlation analysis to improve the evaluation of flow-gating times in radial phase-contrast scans. Quantitatively comparable results (R = 0.92-0.96, n = 9) of flow-related parameters, including mean velocity, mean flow rate, and flow volume, with conventional ECG-gated imaging demonstrated that the proposed method is highly feasible. The radial flow-gating PC imaging method is applicable in carotid arteries. The proposed flow-gating method can potentially avoid the setting up of ECG-related equipment for brain imaging. This technique has potential use in patients with arrhythmia or weak ECG signals.

Physiological noise arising from a variety of sources can significantly degrade the detection of task-related activity in BOLD-contrast fMRI experiments. If whole head spatial coverage is desired, effective suppression of oscillatory physiological noise from cardiac and respiratory fluctuations is quite difficult without external monitoring, since traditional EPI acquisition methods cannot sample the signal rapidly enough to satisfy the Nyquist sampling theorem, leading to temporal aliasing of noise. Using a combination of high speed magnetic resonance inverse imaging (InI) and digital filtering, we demonstrate that it is possible to suppress cardiac and respiratory noise without auxiliary monitoring, while achieving whole head spatial coverage and reasonable spatial resolution. Our systematic study of the effects of different moving average (MA) digital filters demonstrates that a MA filter with a 2 s window can effectively reduce the variance in the hemodynamic baseline signal, thereby achieving 57%-58% improvements in peak z-statistic values compared to unfiltered InI or spatially smoothed EPI data (FWHM = 8.6 mm). In conclusion, the high temporal sampling rates achievable with InI permit significant reductions in physiological noise using standard temporal filtering techniques that result in significant improvements in hemodynamic response estimation., (Copyright © 2011 Wiley Periodicals, Inc.)

Parallel imaging technique using localized gradients (PatLoc) uses the combination of surface gradient coils generating nonbijective curvilinear magnetic fields for spatial encoding. PatLoc imaging using one pair of multipolar spatial encoding magnetic fields (SEMs) has two major caveats: (1) The direct inversion of the encoding matrix requires exact determination of multiple locations which are ambiguously encoded by the SEMs. (2) Reconstructed images have a prominent loss of spatial resolution at the center of field-of-view using a symmetric coil array for signal detection. This study shows that a PatLoc system actually has a higher degree of freedom in spatial encoding to mitigate the two challenges mentioned above. Specifically, a PatLoc system can generate not only multipolar but also linear SEMs, which can be used to reduce the loss of spatial resolution at the field-of-view center. Here, we present an efficient and generalized image reconstruction method for PatLoc imaging using multiple SEMs without explicitly identifying the locations where SEM encoding is not unique. Reconstructions using simulations and empirical experimental data are compared with those using conventional linear gradients to demonstrate that the general combination of SEMs can improve image reconstructions., (Copyright © 2012 Wiley Periodicals, Inc.)

The production and increase of damage points in optical components under high energy repetitive pulsed lasers is closely dependent on the effects of light beam intensity modulation. In the present paper, the appearance of laser-induced damage points on surface of K9 glass was observed. The damage is increased toward center. In this way, the center of the focus of laser beam is fully cracked, and the shell-like factures and the refractive-index changing region, which is caused by phase transition, are arranged outward orderly. The transmittance spectrum through the K9 glass and damage point were measured, indicating that the optical transmittances can reduce by over 20% and the declining rate is related to the area of damage points instead of the wavelength, which means that the full fracture of the material will absorb laser energy completely and is similar to the black body. The laser density detection with CCD shows that the damage points can cause the distortion of laser transmission and the scattering effect plays a major role. This kind of modulation effects by damage points can cause inhomogeneity of the laser light intensity distribution, which can induce diffusion of damage in optical components.

Forsythosides H-J (1-3), three new caffeoyl phenylethanoid glycosides (CPGs), were isolated from the fruits of Forsythia suspense (Thunb.) Vahl., together with six known phenylethanoid glycosides: Forsythoside A (4), Forsythoside F (5), Forsythoside E (6), 2-(3,4-dihydroxyphenyl)ethyl-beta-D-glucopyranoside (7), phenethyl alcohol beta-D-xylo-pyranosyl-(1-->6)-beta-D-glucopyranoside (8) and calceolarioside B (9). Their structures were determined by spectroscopic and chemical methods.

Unlabelled: Our previous fMRI and microdialysis measurements showed that electroacupuncture (EA) at LI4 was effective in alleviating excessive cerebral dopamine release induced by d-amphetamine (AMPH) in rats. We now compare the effect of EA in adjusting excess dopamine release at two stimulating frequencies (2 Hz versus 100 Hz at LI4) and at two acupoints (forepaw (LI4) versus hindpaw (ST36), at 2 Hz). fMRI measurements of relative cerebral blood volume (rCBV) were used to monitor the brain activity of "rest", followed by AMPH challenge, 10 min "rest", and then 20 min of EA., Results: EA at LI4 and ST36 significantly attenuated the AMPH-induced rCBV increases in the striatum, S1 cortex, and thalamus. Frequency: EA at 100 Hz induced greater attenuation of rCBV than EA at 2 Hz in the S1, insula, anterior cingulate cortices, dorsolateral striatum, and thalamus. Acupoints: EA at LI4 modulated a broader area in the medial anterior striatum while EA at ST36 modulated a more site-specific area in the dorsolateral striatum. In the thalamus, EA at LI4 showed greater attenuating effect than EA at ST36 did. However, in the insular cortex, EA at ST36 showed stronger attenuation., Conclusion: EA at both LI4 and ST36 was effective in restoring dopamine homeostasis from an excess state, with the most effective response at LI4 with 100 Hz, while the responses to 2Hz EA at LI4 and ST36 showed slightly different spatial distribution of MR signal. This therefore provided insight into the neurophysiological basis of electroacupuncture effects in cortical and subcortical circuits.

The subcortical response to peripheral somatosensory stimulation is not well studied. Prior literature suggests that somatosensory stimulation can affect dopaminergic tone. We studied the effects of electrical stimulation near the median nerve on the response to an amphetamine-induced increase in synaptic dopamine. We applied the electrical stimulation close to the median nerve 20 min after administration of 3mg/kg amphetamine. We used fMRI and microdialysis to measure markers of dopamine (DA) release, together with the release of associated neurotransmitters of striatal glutamate (Glu) and gamma-aminobutyric acid (GABA). Changes in cerebral blood volume (CBV), a marker used in fMRI, indicate that electrical stimulation significantly attenuated increased DA release (due to AMPH) in the striatum, thalamus, medial prefrontal and cingulate cortices. Microdialysis showed that electrical stimulation increased Glu and GABA release and attenuated the AMPH-enhanced DA release. The striatal DA dynamics correlated with the CBV response. These results demonstrate that electrical stimulation near the median nerve activates Glu/GABA release, which subsequently attenuate excess striatal DA release. These data provide evidence for physiologic modulation caused by electroacupuncture at points near the median nerve.

Multiple receivers can be utilized to enhance the spatiotemporal resolution of MRI by employing the parallel imaging technique. Previously, we have reported the L-curve Tikhonov regularization technique to mitigate noise amplification resulting from the geometrical correlations between channels in a coil array. Nevertheless, one major disadvantage of regularized image reconstruction is lengthy computational time in regularization parameter estimation. At a fixed noise level, L-curve regularization parameter estimation was also found not to be robust across repetitive measurements, particularly for low signal-to-noise ratio (SNR) acquisitions. Here we report a computationally efficient and robust method to estimate the regularization parameter by partitioning the variance of the noise-whitened encoding matrix based on the estimated SNR of the aliased pixel set in parallel MRI data. The proposed Variance Partitioning Regularization (VPR) method can improve computational efficiency by 2-5-fold, depending on image matrix sizes and acceleration rates. Our anatomical and functional MRI results show that the VPR method can be applied to both static and dynamic MRI experiments to suppress noise amplification in parallel MRI reconstructions for improved image quality.

A technique integrating multishot periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) and parallel imaging is presented for diffusion echo-planar imaging (EPI) at high spatial resolution. The method combines the advantages of parallel imaging to achieve accelerated sampling along the phase-encoding direction, and PROPELLER acquisition to further decrease the echo train length (ETL) in EPI. With an eight-element circularly symmetric RF coil, a parallel acceleration factor of 4 was applied such that, when combined with PROPELLER acquisition, a reduction of geometric distortions by a factor substantially greater than 4 was achieved. The resulting phantom and human brain images acquired with a 256 x 256 matrix and an ETL of only 16 were visually identical in shape to those acquired using the fast spin-echo (FSE) technique, even without field-map corrections. It is concluded that parallel PROPELLER-EPI is an effective technique that can substantially reduce susceptibility-induced geometric distortions at high field strength.

A technique suitable for diffusion tensor imaging (DTI) at high field strengths is presented in this work. The method is based on a periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) k-space trajectory using EPI as the signal readout module, and hence is dubbed PROPELLER EPI. The implementation of PROPELLER EPI included a series of correction schemes to reduce possible errors associated with the intrinsically higher sensitivity of EPI to off-resonance effects. Experimental results on a 3.0 Tesla MR system showed that the PROPELLER EPI images exhibit substantially reduced geometric distortions compared with single-shot EPI, at a much lower RF specific absorption rate (SAR) than the original version of the PROPELLER fast spin-echo (FSE) technique. For DTI, the self-navigated phase-correction capability of the PROPELLER EPI sequence was shown to be effective for in vivo imaging. A higher signal-to-noise ratio (SNR) compared to single-shot EPI at an identical total scan time was achieved, which is advantageous for routine DTI applications in clinical practice., ((c) 2005 Wiley-Liss, Inc.)

Parallel MRI techniques reconstruct full-FOV images from undersampled k-space data by using the uncorrelated information from RF array coil elements. One disadvantage of parallel MRI is that the image signal-to-noise ratio (SNR) is degraded because of the reduced data samples and the spatially correlated nature of multiple RF receivers. Regularization has been proposed to mitigate the SNR loss originating due to the latter reason. Since it is necessary to utilize static prior to regularization, the dynamic contrast-to-noise ratio (CNR) in parallel MRI will be affected. In this paper we investigate the CNR of regularized sensitivity encoding (SENSE) acquisitions. We propose to implement regularized parallel MRI acquisitions in functional MRI (fMRI) experiments by incorporating the prior from combined segmented echo-planar imaging (EPI) acquisition into SENSE reconstructions. We investigated the impact of regularization on the CNR by performing parametric simulations at various BOLD contrasts, acceleration rates, and sizes of the active brain areas. As quantified by receiver operating characteristic (ROC) analysis, the simulations suggest that the detection power of SENSE fMRI can be improved by regularized reconstructions, compared to unregularized reconstructions. Human motor and visual fMRI data acquired at different field strengths and array coils also demonstrate that regularized SENSE improves the detection of functionally active brain regions., (2005 Wiley-Liss, Inc)

In this study, we arbitrarily classified the morphological changes of sperm under hypo-osmotic condition and compared the results with four different sperm separation techniques. The morphology of classification ranged from a good swelling (SG 3 > SG 2 > SG 1), to non-swelling but reactive (SG 0-R), and completely non-swelling (SG 0). Thirty fresh semen from patients were divided into 4 groups and each processed by washing, swim up, 2-layer column and real time micro-separation system. The prevalent patterns of the swollen sperm in sequence after treatment was SG 0 > SG 1 > SG 3 > SG2 > SG 0-R in fresh semen, and the proportion of SG 0 was almost half of the total % HOS test results. However, SG 3 became the most common swollen form with a significant increase in number with any method of sperm preparation after treatment. The real time technique yielded the highest % rate of SG 3 type of swollen spermatozoa and was the richest in concentration (53+/-3.9%, P < 0.05) as compared with that of swim up (26+/-4.6%), 2-layer (20+/-4.4%), sperm washing (23+/-3.9%), and fresh semen (17+/- 2.8%), respectively. By contrast, 2-layer collected more number of SG0-R (5.3+/-1.2%, P < 0.05) pattern of spermatozoa when compared to real time and swim up. A positive correlation (r = 0.81, P < 0.002) was shown between the % total HOS spermatozoa and total motility of fresh semen but not with morphology. Collectively, an abnormally functional sperm may exist in almost half of a total sperm count from men. It would appear that a better potential fertilization capacity may reside in the more swollen sperm from HOS test than the less swollen sperm and that may be more related with the motility rather than the morphology. The HOS classification and grading system appears valuable in further evaluating sperm quality.

In this work the feasibility of separating fat and water signals using the balanced steady-state free precession (SSFP) technique is demonstrated. The technique is based on the observation (Scheffler and Hennig, Magnetic Resonance in Medicine 2003;49:395-397) that at the nominal values of TE = TR/2 in SSFP imaging, phase coherence can be achieved at essentially only two orientations (0 degrees and 180 degrees ) relative to the RF pulses in the rotating frame, under the assumption of TR << T2, and independently of the SSFP angle. This property allows in-phase and out-of-phase SSFP images to be obtained by proper choices of the center frequency offset, and thus allows the Dixon subtraction method to be utilized for effective fat-water separation. The TR and frequency offset for optimal fat-water separation are derived from theories. Experimental results from healthy subjects, using a 3.0 Tesla system, show that nearly complete fat suppression can be accomplished., (Copyright 2004 Wiley-Liss, Inc.)

Background and Purpose: The purpose of this study was to reevaluate the usefulness of relative maximum signal drop (rMSD), as compared to relative cerebral blood volume (rCBV) and cerebral blood flow (rCBF), in dynamic susceptibility contrast magnetic resonance imaging (MRI)., Methods: Twenty-five patients (11 with cerebral gliomas and 14 with infarcts of middle cerebral arterial territories) were included. The rMSD values were measured from 83 regions of interest and compared with measurements from corresponding rCBV and rCBF maps., Results: In stroke patients, rMSD correlated strongly with rCBF (r = 0.96) but only fairly with rCBV (r = 0.69). The absence of an association between rMSD and rCBV was evident in regions of increased contrast bolus dispersion. In glioma patients, the correlation of rMSD with rCBF (r = 0.85) was similar to that of rMSD with rCBV (r = 0.80). The interparameter associations were well predicted by computer simulations., Conclusions: The authors conclude that rMSD is as useful as rCBF under a variety of pathophysiological conditions, whereas in conditions with normal mean transit time, such as brain tumors, rMSD provides equivalent blood volume information to rCBV. The simplicity of rMSD maps could lead to the increased use of perfusion-weighted MRI.

Glucose and insulin stimulate leptin gene expression in vitro and in vivo. To identify cis-elements that are responsible for the glucose and insulin effects, mouse 3T3-L1 adipocytes were transiently transfected with reporter constructs with serial deletions in mouse ob gene promoter. The cis-elements were identified with Gel mobility shift assays (GMSA), DNase I footprint assays and PCR mediated site-directed mutation assays. Transient transfections detected a negative cis-acting element, a glucose-responsive element (GLRE), and an insulin-responsive element (IRE) in the region from -1 719 bp to -1 452 bp of mouse ob gene. This region does not contain any known GLRE or IRE. GMSA identified a DNA binding protein which specifically binds a native probe prepared from mouse ob gene promoter (-1 719 bp/-1 452 bp), and the binding was repressed by glucose or insulin. DNase I footprint assays and PCR mediated site-directed mutations assays identified that the binding motif AGCAAAA, spanning -1 698 bp to -1 692 bp of the mouse ob gene promoter, was responsible for the effects of glucose and insulin on ob gene expression. These studies suggest that a negative cis-acting element is located between -1 719 bp and -1 452 bp of the mouse ob gene promoter, and glucose and insulin simulate mouse ob gene expression by repressing the binding of a transcription factor to this element. This element, AGCAAAA, spanning -1 698 bp to -1 692 bp is a novel GLRE and IRE.